···

       
446
       
446
       
 
       
  <literal>stdenv</literal>; the formed changes the C compiler, and

     

       
447
       
447
       
 
       
  the latter adds additional packages to the front of

     

       
448
       
448
       
 
       
  <literal>stdenv</literal>’s initial <envar>PATH</envar>, allowing

     

       
449
       
449
       
-
       
  tools to be overriden.</para>

     

       
449
       
449
       
+
       
  tools to be overridden.</para>

     

       
450
       
450
       
 
       


     

       
451
       
451
       
 
       
  <para>For instance, the package <varname>strategoxt</varname>

     

       
452
       
452
       
 
       
  doesn’t build with the GNU Make in <literal>stdenv</literal>

     

···

       
56
       
56
       
 
       
<para>Often it is necessary to override or modify some aspect of the

     

       
57
       
57
       
 
       
build.  To make this easier, the standard environment breaks the

     

       
58
       
58
       
 
       
package build into a number of <emphasis>phases</emphasis>, all of

     

       
59
       
59
       
-
       
which can be overriden or modified individually: unpacking the

     

       
59
       
59
       
+
       
which can be overridden or modified individually: unpacking the

     

       
60
       
60
       
 
       
sources, applying patches, configuring, building, and installing.

     

       
61
       
61
       
 
       
(There are some others; see <xref linkend="ssec-stdenv-phases"/>.)

     

       
62
       
62
       
 
       
For instance, a package that doesn’t supply a makefile but instead has

     
···

       
233
       
233
       
 
       
the binaries).  Furthermore, it allows a nicer presentation of build

     

       
234
       
234
       
 
       
logs in the Nix build farm.</para>

     

       
235
       
235
       
 
       


     

       
236
       
236
       
-
       
<para>Each phase can be overriden in its entirety either by setting

     

       
236
       
236
       
+
       
<para>Each phase can be overridden in its entirety either by setting

     

       
237
       
237
       
 
       
the environment variable

     

       
238
       
238
       
 
       
<varname><replaceable>name</replaceable>Phase</varname> to a string

     

       
239
       
239
       
 
       
containing some shell commands to be executed, or by redefining the

     

···

       
873
       
873
       
 
       
be passed your customised instance.  (However, the value

     

       
874
       
874
       
 
       
<literal>pkgs.emacs</literal> in

     

       
875
       
875
       
 
       
<varname>nixpkgs.config.packageOverrides</varname> refers to the

     

       
876
       
876
       
-
       
original rather than overriden instance, to prevent an infinite

     

       
876
       
876
       
+
       
original rather than overridden instance, to prevent an infinite

     

       
877
       
877
       
 
       
recursion.)</para>

     

       
878
       
878
       
 
       


     

       
879
       
879
       
 
       
</section>